Professor Sylvia Ceyer continues her discussion of acid-base equilibrium, diving into buffers. The lecture concludes with the Henderson-Hasselbalch equation and its use in designing a buffer.
In this introductory lecture, Professor Sylvia Ceyer introduces those throughout history who have contributed to the atomic theory of matter, beginning with Aristotle and Democritus, and ending with the work of Lavoisier, Proust, and Dalton. After disussing scanning tunnelling microscopy, Professor Ceyer moves to the major advances in chemistry at the end of the 19th century. These include Newtonian mechanics, thermodynamices, statistical mechanics, and classical electromagnetism. The lecture ends with a non-"classical" observation that changed the trajectory of chemistry: the discovery of the electron.
Structure of the Atom: A Conundrum. The work of E. Rutherford, 1911, lead to the discovery of the nucleus. In this lecture, Professor Sylvia Ceyer begins by explaining the backscattering experiment that lead to this key discovery in the early 20th century. She then moves on to a classical description of the atom, including coulombic interaction and the classical equation of motion (Newton's Second Law). The lecture ends with discussion of the wave-particle duality of matter and radiation, highlighting the wave nature of light and the periodic variation of an electromagnetic field.
Professor Sylvia Ceyer devotes this lecture to discussing the wavelike properties of radiation. She covers oscillation vs. propagation in light, calculating the speed of a wave, and the visible light spectrum. She then moves on to the wave nature of light, highlighting a few new terms including superposition, constructive, and destructive interference. In conclusion, the wavelike properties of radiation are discussed as they relate to Young's two slit experiment. The general conditions for constructive interference and destructive interference are identified.
In this lecture Professor Sylvia Ceyer moves on from the wavelike properties of light, to the particle-like nature of light. To do so she covers the photoelectric effect in detail, discussing threshold frequency and kinetic energy vs. frequency. Planck's constant is discussed. The lectures concludes with a discussion of photon momentum and its relation to wavelength.
This lecture is devoted to the electron diffraction experiment of 1927, where the wavelike nature of electron beams was experimentally established, thus supporting an underlying principle of quantum mechanics. Professor Sylvia Ceyer discusses how to calculate λ from θ, de Broglie wavelength, and concludes with Schrodinger's equation of motion for matter waves.
Professor Sylvia Ceyer focuses on the hydrogen atom, beginning with a discussion of electron binding energy to the nucleus. Other topics covered are verification of energy levels for the H atom (including photon emission, transitions between states, and photon emission) as well as the wavefunctions for an H atom. The stations state wavefunction is explained and the three quantum numbers used to describe a wave in 3D – principle quantum number, angular momentum quantum number, and magnetic quantum number.
Professor Sylvia Ceyer highlights the hydrogen atom wavefunctions, including orbitals and degeneracy. The shapes of an H atom orbitals are then explained, including probability density, radial probability distribution, s wavefunctions, and radial nodes. The lecture concludes with Bohr's Model and the Uncertainty Principle.
Professor Sylvia Ceyer focuses on p-orbitals, describing nodal planes, angular nodes, and radial probability distributions. The conversation continues forward to wavefunctions for multielectron atoms, beginning with an explanation of electron configuration. The Pauli and spin exclusion principle is covered, and the lecture concludes with a discussion of one electron wavefunctions for multielectron atoms.
In this lecture Professor Sylvia Ceyer covers the electron structure of multielectron atoms, beginning with simple electron configurations. The Aufbau Principle is explained, as well as the Pauli Exclusion Principle and Hund's Rule. Core electrons and valence electrons are discussed, concluding with electron configurations of ions and photoelectron spectroscopy.
Professor Sylvia Ceyer devotes this lecture to a discussion of the periodic table, beginning with its history. Period trends are covered, including ionization energy, electron affinity, elecrtonegativity, and atomic sizes. The lecture concludes with isoelectronicity, where two molecular entities have the same number of valence electrons and the same structure, regardless of the nature of the elements involved.
Professor Sylvia Ceyer discusses the energy of interaction in nuclear-nuclear repulsion, electron-electron repulsion, and electron-nuclear attraction.
Professor Sylvia Ceyer explains the steps required to create a Lewis structure, using the cyanide ion and thionyl chloride as examples. She discusses formal charge within a molecule, skeletal structure of chain molecules, and resonance structures using the nitrate ion as an example.
Professor Sylvia Ceyer breaks down the Octet Rule covering molecules with an odd number of valence electrons, octet deficient molecules, and valence shell expansion. She concludes with ionic bonds as a classical model and mechanism discussing the Harpoon Mechanism, limitations of the model, and energy of interaction vs. the radius of an electron.
Professor Sylvia Ceyer covers the molecular orbital theory, beginning with a discussion of some key topics including bonding orbitals, antibonding orbitals, electron configurations, and bond order. Using a wealth of examples to depict molecular orbitals (MOs) formed by the linear combination of atomic orbitals (LCAO), she concludes with heteronuclear diatomics.
Professor Sylvia Ceyer covers valence bond theory and hybridization in atomic molecules. A number of examples are used to depict sp3 hybridization, sp2 hybridization, and sp hybridization.
Professor Sylvia Ceyer discusses hybridization and chemical bonding. Using methyl nitrate as an example, Professor Ceyer describes how to find the lowest energy Lewis structure and explains bond symmetry, hybrid orbitals, and atomic orbitals. Moving onto intramolecular interactions, the discussion breaks down the origin of a bad hair day: hydrogen bonding, water, and keratin.
Professor Sylvia Ceyer discusses bond enthalpy and the enthalpy of endothermic/exothermic chemical reactions. The heat of formation is defined as Professor Ceyer explains Hess's Law which is used to predict the enthalpy change and conservation of energy, regardless of the path through which it is to be determined. The lecture concludes with a discussion of thermodynamics and spontaneous chance, specifically Gibbs free energy and the concept of entropy.
Professor Sylvia Ceyer explains the standard Gibbs free energy of formation and its relationship to thermodynamic stability. The Second Law of Thermodynamics is defined as it relates to controlling spontaneity with temperature. The lecture concludes by defining the thermodynamic equilibrium constant and the reaction quotient/direction of change in a chemical equilibrium.
Professor Sylvia Ceyer discusses the nature of chemical equilibrium as it relates to free energy, the reaction quotient, and the relationship between K and Q. The meaning of K is further clarified and the external effects on K are identified, from adding and removing reagents to changes associated with the Principle of Le Chatelier.
Professor Sylvia Ceyer continues her discussion on chemical equilibrium and external effects such as a change in volume, adding inert gas, and a change in temperature. Parameters are set for maximizing the yield of a reaction, and the Principle of Le Chatelier's is returned to. Hemoglobin is used as an example involved in a series of equilibrium reactions in response to oxygen pressure.
Professor Sylvia Ceyer discusses the classification of acids and bases as they are defined by Arrhenius, Bronsted-Lory, and Lewis acid/base. The pH function (and pOH function) are defined as they relate to the strength of acids and bases (in water). Professor Ceyer then runs through the types of acid-base problems and concludes by discussing equilibrium involving weak acids.
Professor Sylvia Ceyer continues her discussion of acid-base equilibrium, diving into buffers. The lecture concludes with the Henderson-Hasselbalch equation and its use in designing a buffer.
Professor Sylvia Ceyer discuses titrations involving a strong acid and a strong base. Defining the point and equivalence and the end point. The lecture continues with a focus on calculating points on a pH curve, specifically calculating pH before the equivalence point, calculating volume of HCl needed to reach equivalence point, and calculating pH after the equivalence point. Finally, Professor Ceyer discusses characteristics of titration curves for weak acid/strong base and for weak base/strong acid solutions.
Professor Sylvia Ceyer concludes her discussion of acid/base titrations and moves onto the guidelines for assigning oxidation number. After defining the terms oxidation, reduction, oxidizing agent, and reducing agent, Professor Ceyer explains how to balance a redox reaction.
After a discussion of electrochemical cells, Professor Sylvia Ceyer defines the points of oxidation and reduction in a battery as the anode and cathode, respectively. She discusses the application of Faraday's Law and its relationship to electrochemical cells. Finally, the relationship between cell potential and Gibbs free energy is highlighted.
Professor Sylvia Ceyer begins by adding and subtracting half-cell reactions (a continuation of her prior lecture on oxidation/reduction). The Nernst Equation is introduced, which can be used to determine the equilibrium reduction potential of a half cell in an electrochemical cell.
Professor Sylvia Ceyer introduces transition metals and the formation of coordination complexes. The Chelate effect is defined and the difference between geometric isomers and optical isomer (enantiomers) is discussed. The discussion concludes with d orbitals and d-electron counting in coordination complexes.
Professor Sylvia Ceyer introduces the class to crystal field theory and ligand field theories. Several terms are defined, including octahedral field splitting energy, and the lecture concludes by using the octahedral crystal field splitting diagram with a few examples.
Professor Sylvia Ceyer discusses the Valence Shell Electron Pair Repulsion (VSEPR) theory and its use with predicting the shapes of individual molecules, based upon their extent of electron-pair electrostatic repulsion. The RSEPR Rules are defined and the shapes based on VSEPR theory rationalized using atomic size and bond length.
Professor Sylvia Ceyer discusses the rates of chemical reactions, factors affecting rates of reactions, measuring reaction rates, and common rate expressions. The discussion then moves to the rate laws and highlights the order of reaction in reactants/products, overall reaction order, units for k, and integrated rate laws (specifically, first order half-life).
Professor Sylvia Ceyer covers radioactive decay and its various uses in modern medicine. Second order half-life, as a second order integrated rate law, is then discussed. The lecture concludes with the overlap of kinetics and chemical equilibrium: the equilibrium constant, elementary reactions, and an example, the decomposition of ozone.
Professor Sylvia Ceyer investigates chemical reaction mechanisms: rate, order, molecularity, steady-state approximation, and rate determing steps.
Professor Sylvia Ceyer discusses the effects of temperature on reaction rates, including in her lecture the Arrhenius equation, activation energy, reaction coordinate, and the activation complex.
Professor Sylvia Ceyer discusses the kinetics of catalysis and the various types of catalysts: homogeneous, hetergenerous, and the catalysts of life, enzymes. The lecture then shifts to focus on enyme catalysis and its various components: substrates, active sites, and enzyme inhibition.
Review. Professor Sylvia Ceyer reviews the main topics covered throughout the second half of the course including kinetics, transition metals, VSEPR theory, acid-base equilibrium, chemical equilibrium, and oxidation/reduction. Professor Ceyer uses the case study of methionine synthase to supplement the discussion.
Professor Sylvia Ceyer covers crystal field theory in both the tetrahedral case and the square planar case. The discussion then moves to the spectrochemical series and strong/weak field ligands. A conversation on magnetism, both paramagnetic and diamagnetic, in transition metals concludes the lecture.